TreeView控件绑定数据库

<form id="form1" runat="server">
<div>
<h1>两个表</h1>
<asp:TreeView ID="TreeView1" runat="server">
<HoverNodeStyle Font-Underline="true" ForeColor="Window" />
<NodeStyle Font-Names="Tahoma" Font-Size="8pt" ForeColor="Black" HorizontalPadding="2px" NodeSpacing="0px" VerticalPadding="2px"/>
<ParentNodeStyle Font-Bold="False" />
<SelectedNodeStyle BackColor="Red" Font-Underline="False" HorizontalPadding="0px" VerticalPadding="0px" />
</asp:TreeView>
<br />
<asp:Button ID="Button1" runat="server" Text="ShowTwoTable" OnClick="Button1_Click"/>
<br /><br /><hr />
<h1>一个表</h1>
<asp:TreeView ID="TreeView2" runat="server"></asp:TreeView>
<br />
<asp:Button ID="Button2" runat="server" Text="ShowOne" OnClick ="Button2_Click" />
</div>
</form>

#region 一个表的显示
protected void Button2_Click(object sender, EventArgs e)
{
PopulateMenu();
}
//use the linq to sql
MynodeDataContext db = new MynodeDataContext();
private void PopulateMenu()
{
List<NodeSubNode> allMenu = new List<NodeSubNode>();
allMenu = db.NodeSubNodes.ToList();
CreateTreeView(allMenu, 0, null);
}

private void CreateTreeView(List<NodeSubNode> source, int parentID, TreeNode parentNode)
{
List<NodeSubNode> newSource = db.NodeSubNodes.Where(a => a.SubjectId.Equals(parentID)).ToList();
foreach (var i in newSource)
{
TreeNode newnode = new TreeNode(i.Name, i.Id.ToString());
if (parentNode == null)
{
TreeView2.Nodes.Add(newnode);
}
else
{
parentNode.ChildNodes.Add(newnode);
}
CreateTreeView(source, i.Id, newnode);
}
}
#endregion